The plasma display panel (hereafter referred to as PDP) generates ultra-violet ray in gas discharge, and excites phosphors to emit light by the ultra-violet ray to perform image displaying.
The plasma display panels are roughly divided into AC powered and DC powered in driving method, and into surface discharge and counter discharge in discharging method. Currently, however, surface discharge AC powered with three-electrode structure has become the mainstream technology due to capabilities for high definition display, large-sized screen, simple structure and easy manufacturing method.
The AC powered PDP consists of a front substrate and a rear substrate. The front substrate is a substrate made of glass or the like on which: display electrodes including scan electrodes and sustain electrodes; light-shields between adjacent display electrodes; a dielectric layer covering the electrodes; and a protective layer to cover the layers further, are formed. The rear substrate is a substrate made of glass or the like on which: a plurality of address electrodes crossing the display electrodes on the front substrate; a dielectric layer covering the electrodes; and ribs on the dielectric layer are formed. The front substrate and rear substrate are positioned facing each other so as to form discharge cells at crossings of discharge electrodes and data electrodes, and the discharge cells are provided with phosphor layers internally.
The display electrode is provided with a transparent electrode and a bus electrode. The bus electrode has a black electrode to block incoming light reflection and a low resistance metal-rich electrode.
More recently, the PDP attracts increasing attention among flat panel display technologies and is used widely as a display device for a place crowded with many people or to enjoy images at a large screen home-theater. This is because the PDP can respond to display faster and can be produced in large sizes easier than LCD, with wide viewing angles and a high picture quality due to self-lighting.
As to the configuration of black electrodes to compose the display electrode and the light-shield provided between the display electrodes, an example is disclosed in Japanese Patent Unexamined Publication No. 2002-83547: these electrodes are formed of a plurality of layers on the substrate and one of a plurality of the layers is a black layer, having a higher sheet resistance than the other layers, which forms the light-shields as well as the black electrodes integrally.
However, when the black layer is commonly used to the light-shield, a smaller resistance of the black layer would increase capacitance in the light-shield, causing an increase in power consumption. Contrarily, a larger resistance of the black layer would increase the resistance of transparent electrode composing the display electrode, causing a critical problem of poor image quality.